Supplemental Cash Flow Information - Change in Certain Working Capital Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Supplemental Cash Flow Elements [Abstract]
Accounts and notes receivable	$ (22,522)	$ (20,511)	$ (17,562)
Income taxes receivable/payable, net	(265)	4,626	(13,700)
Accounts payable	(7,259)	(966)	(2,696)
Accrued employee compensation and benefits	3,175	(1,056)	6,309
Other accrued liabilities	12,645	(6,100)	(7,087)
Other, net	(6,282)	(10,854)	(5,698)
Total	$ (20,508)	$ (34,861)	$ (40,434)

The increase (decrease) during the reporting period of the sum of amounts due within one year (or one business cycle) from customers for the credit sale of goods and services; and from note holders for outstanding loans.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

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- Definition

The increase (decrease) during the reporting period in the aggregate amount of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business.

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- Definition

The increase (decrease) during the reporting period in the aggregate amount of obligations related to services received from employees, such as accrued salaries and bonuses, payroll taxes and fringe benefits.

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- Definition

The increase (decrease) during the reporting period in the amounts payable to taxing authorities for taxes that are based on the reporting entity's earnings, net of amounts receivable from taxing authorities for refunds of overpayments or recoveries of income taxes.

+ References

No definition available.

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- Definition

The increase (decrease) during the reporting period of all assets and liabilities used in operating activities.

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- Definition

The increase (decrease) during the reporting period in other expenses incurred but not yet paid.

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Amount of increase (decrease) in operating assets after deduction of operating liabilities classified as other.

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No definition available.

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